Flexible pipe carcass forming apparatus

ABSTRACT

An apparatus for forming a carcass for encasing a tubular member including a driven rotor ( 20 ) having a front face rotatable about a pivot axis and a spool mandrel ( 38 ) positioned eccentrically on the driven rotor ( 20 ). The spool mandrel ( 38 ) is adapted to rotatably mount a roll of coiled strip material ( 32 ). The rotor ( 20 ) includes at least one counterweight ( 60 ) mounted on the front face that is dynamically movable to at least partially balance the changing weight of the roll of strip material as the strip material ( 32 ) is removed from the roll. At least one pusher roll assembly ( 75 ) is mounted on the front face and contacts a portion of the strip material ( 32 ) to partially deform the coiling of the strip material as the material is removed from the roll. An anti-kink roll assembly ( 90 ) prevents kink deformation of the strip material ( 32 ) during the formation of the carcass.

PRIORITY CLAIM

This application claims the benefit of priority of U.S. ProvisionalApplication Ser. No. 61/546,055, entitled “Flexible Pipe Carcass FormingApparatus,” filed Oct. 11, 2011, and further claims the benefit ofpriority of U.S. Provisional Application Ser. No. 61/554,639, entitled“Flexible Pipe Carcass Forming Apparatus,” filed Nov. 2, 2011, each ofthe foregoing disclosures of which are hereby incorporated by referencein their entirety.

BACKGROUND

The present invention generally relates to machines for formingmaterials and armor structures to protect tubular members. Moreparticularly, the present application relates to a carcass-formingmachine for encasing a tubular member.

Carcass machines produce a carcass of a flexible pipe. A main purpose ofthe carcass is to prevent the pipe from collapsing under externalpressure, e.g., due to water pressure and mechanical crushing duringproduction and installation of the pipe. The collapse strength generallydepends on the mechanical integrity of the metal carcass which shouldwithstand the force of the external pressure.

Carcass machines may produce the armor carcass by the process of rollforming and winding of sheet metal strips. For example, a carcassmachine may cold-form a flat steel (or other material) strip into aninterlocking structure.

Typically, a flat strip of material such as steel is pulled off of acoil and is run through a series of deforming operations to form aprofile of the interlocking structure. These operations are performed bypressers or rollers that gradually change the profile of the strip, andsubsequent to the generation of such a strip, a winding step is usedduring the manufacture of the carcass for the flexible pipe body. Insome examples, the carcass strip is formed into a profile having hookand valley regions, so that as the strip of material is wound, adjacentwindings are interlocked together by nesting hook and valley regions.During manufacture, the shaped strip may be wound at an angle, so thatthe flexibility of the metal carcass produced allows the metal carcasssufficient flexibility.

Machines that are typically used to form the carcass structures arelarge, and they require that the metal strip is fed off of a stationaryspool or coil. For especially large carcass structures, such as thoseused to armor wide-diameter tubular structures such as those used inultra-deepwater oil pumping operations, much wider and heavier metalstrip material is required to be used. Because the more substantialmetal strip material is extremely rigid and heavy, it may be impracticalto mount the coil of strip material and thread it toward a moving rotorfor profile formation.

SUMMARY

In one aspect of the present invention, an apparatus for forming acarcass for encasing a tubular member includes a driven rotor having afront face rotatable about a pivot axis and a spool mandrel positionedeccentrically on the driven rotor. The spool mandrel is adapted torotatably mount a roll of coiled strip material. The rotor includes atleast one counterweight mounted on the front face that is dynamicallymovable to at least partially balance the changing weight of the roll ofstrip material as the strip material is removed from the roll. At leastone pusher roll assembly is mounted on the front face and contacts aportion of the strip material to partially deform the coiling of thestrip material as the material is removed from the roll.

In another aspect of the invention, an anti-kink roll assembly ismounted to the front face for preventing kink deformation of the stripmaterial during the formation of the carcass.

In yet another aspect of the invention, at least one clamping assemblyis mounted to the strip material to control the uncoiling of the stripmaterial from the roll and to prevent unthreading of the machine.

In a further aspect of the invention, a roll of coiled strip material isremovably and rotatably mounted to the spool mandrel. The roll ofmaterial may be interchanged with other rolls on the rotor.

In yet another aspect of the invention, a roller assembly is mounted tothe front face for pre-deforming the strip material prior to feeding thestrip material into profile-forming roller assemblies.

Other systems, methods, features and advantages of the invention willbe, or will become, apparent to one with skill in the art uponexamination of the following figures and detailed description. It isintended that all such additional systems, methods, features andadvantages be within the scope of the invention, and be encompassed bythe following claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be better understood with reference to the followingdrawings and description. The components in the figures are notnecessarily to scale, emphasis instead being placed upon illustratingthe principles of the invention. Moreover, in the figures, likereferenced numerals designate corresponding parts throughout thedifferent views.

FIG. 1 is a schematic diagram illustrating a frontal view of anembodiment of the apparatus of the present invention.

FIG. 2 is a schematic diagram illustrating a perspective view of theapparatus of FIG. 1.

FIG. 3 is a schematic diagram illustrating an additional perspectiveview of the apparatus of FIG. 1.

FIG. 4 is a schematic diagram illustrating a side view of the apparatusof FIG. 1.

FIG. 5 is a schematic diagram illustrating features of an anti-kink rollassembly of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now to FIGS. 1-5 of the drawings, a carcass-forming machine 10is shown having a main rotor 20 that is mounted for rotatable movementaround an axis 23. Conventional profile-forming tooling is shown at 44near the axis 23 of the rotor 20 that forms strip material 32 into agenerally S-shaped profile for interlocking in a helical and tubulararmor structure as may be known in the art.

The rotor 20 includes a spool mandrel 38 that may rotatably andremovably receive transferable spools 30 of strip material 32. Anexample is a coil of strip metal 32 in a 3-meter OD package. The spoolmandrel 38 and the spool 30, when mounted, rotate around the axis 23along with the rotor 20.

The transferable mandrel allows for a complete transfer of coil packsfrom the rewind line onto the profiling machine front face 22. In normalpractice, the coil pack only is lifted from the rewind line and centercore is placed onto the front plate chuck. This introduces the abilityfor the coil to unwind, lose proper tension and pose a great safetyrisk. A transferable mandrel allows for the pack to be wound safely andefficiently on the rewind line. The chuck shaft, material and sideplates will then be removed from the rewinder and accepted onto themachine front face 22. This facilitation would be very similar tomachine tools in operation and locking mechanism. With control over thecoil pack during this move, the operator will be able to move the entirepack in a more expedient and safe manner. The empty mandrel from themachine then can replace the one taken from the rewinder. A thirdmandrel will allow for continual transference of empty/full packs withminimal downtime.

In order to balance the extreme eccentric rotary weight of the spool 30of the strip material 32, one or more counterweight masses 60 aremounted to the front face 22 of the rotor 20. In the present embodiment,two counterweights 60 are shown that move along ballscrew structures 61along chords of the rotor 20 utilizing traversing motors 62, as shown inFIG. 1. The weights 60 move automatically to correct for the eccentricrotation of the rotor 20 as the weight of the transferable spool 30 isreduced as material is unwound therefrom during the profile-formingprocess.

If the strip 32 is cut for changeover or any other circumstance, one ormore string up clamps 70 would be engaged to prevent any unnecessarymovement of the cut ends. A clamp above the coil pack would prevent thestrip 32 from backing through the pusher rollers 75 to the pipe. Anotherclamp near the coil spool would prevent the material from loosening onthe coil pack which results in both a safety risk and coil changeover.

To facilitate the deformation of the coiled material into an unwoundstate and to allow for improved feeding into the apparatus such as theflyer bow strip guide 50, a roller assembly noted as a pusher andstraightener roller assembly 75 may be used to unwind the material fromthe spool 30. A dancer roller 52, as shown in FIG. 1, facilitatesfeeding into the forming roller apparatus 80. The pusher andstraightener assemblies are utilized to help facilitate safe andefficient string up of the machine. A motorized three roller assemblyassists in feeding the strip material 32 to the next process step on thetooling plate. The operator would then be allowed to handle a controlledamount of strip 32 as required to thread up the tooling.

Finally, an anti-kink roll assembly 90 is used just before the profileinterlocking process near the axis 23 of the apparatus in order toprevent kinking of the profile. During the formation of a fullyinterlock carcass profile, several progressive steps are taken toachieve the proper dimensions. In some instances, there is a tendency tohave a tight bend of the strip 32 which creases rather than forms a fullradius. The unsupported strip, due to the imposed forces, may buckle.The primary area for this to occur is during the final folding orinterlocking operation when the side of the preformed strip 32 is beingrolled from a raised position to a folded down, interlocking position.This tendency may be exacerbated due to the strip 32 being in tensionfrom both the pre-forming of its cross-section plus the longitudinalpreforming while being wound around the support mandrel to form the pipediameter.

To reduce this tendency to buckle or kink during this process step, theanti-kink roller 90 adds shaped support to an inner area of a foldradius, such as the fold radius 39 of FIG. 5, to allow the strip 32 tofully form the desired radius bend or fold over, rather than have atendency to crease or kink. In the embodiment of FIG. 5, the exemplaryanti-kink roller 90 comprises a series of shaped roller bearings, or abushing, held in position along the strip axis 23 on the mandrel via abracket arrangement 94. The anti-kink roller 90 is positioned to offerthe shaped support to the inner area of the fold radius 39, and inparticular, the bracket arrangement 94 is angled to allow the rollers tocontact the inner radius 39 of the wound strip 32 prior to the fold overpoint, as shown in FIG. 5. Therefore, the anti-kink roller 90advantageously differs from previous techniques for folding stripmaterial that utilize a shaped pressure roll that matches the outsideform of the overall fold, but lacks an inner radius support andtherefore is subjected to kinking.

While various embodiments of the invention have been described, theinvention is not to be restricted except in light of the attached claimsand their equivalents. Moreover, the advantages described herein are notnecessarily the only advantages of the invention and it is notnecessarily expected that every embodiment of the invention will achieveall of the advantages described.

1-15. (canceled)
 16. An apparatus for forming a carcass for encasing atubular member, said apparatus comprising: a driven rotor having a frontface, said driven rotor rotatable about a pivot axis; a spool mandrelpositioned eccentrically on said driven rotor, said spool mandreladapted to rotatably mount a roll of coiled strip material; said rotorincluding at least one counterweight mounted on said front face formovement relative to said pivot axis, said at least one counterweightbeing dynamically movable to at least partially balance the changingweight of said roll of strip material as said strip material is removedfrom said roll; and at least one pusher roll assembly mounted on saidfront face and contacting a portion of said strip material to partiallydeform the coiling of said strip material as said material is removedfrom said roll.
 17. The apparatus of claim 16 further comprising ananti-kink roll assembly for preventing kink deformation of said stripmaterial during the formation of said carcass.
 18. The apparatus ofclaim 17 wherein said anti-kink roll assembly comprises a series ofshaped roller bearings that contact an inner radius of said strip priorto a fold over point.
 19. The apparatus of claim 18 wherein said seriesof shaped roller bearings are positioned along a strip axis via abracket arrangement.
 20. The apparatus of claim 16 further comprising atleast one clamping assembly mounted to said strip material to controlthe uncoiling of said strip material from said roll.
 21. The apparatusof claim 16 further comprising at least one clamping assembly mounted tosaid front face and interfacing with said strip material to control theuncoiling of said strip material from said roll.
 22. The apparatus ofclaim 16 wherein said roll of coiled strip material is removably androtatably mounted to said spool mandrel.
 23. The apparatus of claim 16further comprising a roller assembly mounted to said front face forpre-deforming said strip material prior to feeding said strip materialinto profile-forming roller assemblies, wherein said profile-formingroller assemblies are adapted to form said strip material into anS-shape capable of interlocking with an adjacently formed profile edge.24. An apparatus for forming a carcass for encasing a tubular member,said apparatus comprising: a driven rotor having a front face, saiddriven rotor rotatable about a pivot axis; a spool mandrel positionedeccentrically on said driven rotor, said spool mandrel adapted torotatably mount a roll of coiled strip material; and an anti-kink rollassembly for preventing kink deformation of said strip material duringthe formation of said carcass, wherein said anti-kink roll assemblycomprises a series of shaped roller bearings that contact an innerradius of said strip prior to a fold over point.
 25. The apparatus ofclaim 24 further comprising at least one counterweight mounted on saidfront face of said rotor for movement relative to said pivot axis, saidat least one counterweight being dynamically movable to at leastpartially balance the changing weight of said roll of strip material assaid strip material is removed from said roll.
 26. The apparatus ofclaim 24 further comprising at least one pusher roll assembly mounted onsaid front face and contacting a portion of said strip material topartially deform the coiling of said strip material as said material isremoved from said roll.
 27. The apparatus of claim 24 wherein saidseries of shaped roller bearings are positioned along a strip axis via abracket arrangement.
 28. The apparatus of claim 24 further comprising atleast one clamping assembly mounted to said front face and interfacingwith said strip material to control the uncoiling of said strip materialfrom said roll.
 29. The apparatus of claim 24 wherein said roll ofcoiled strip material is removably and rotatably mounted to said spoolmandrel.
 30. The apparatus of claim 24 further comprising a rollerassembly mounted to said front face for pre-deforming said stripmaterial prior to feeding said strip material into profile-formingroller assemblies, wherein said profile-forming roller assemblies areadapted to form said strip material into an S-shape capable ofinterlocking with an adjacently formed profile edge.
 31. An method forforming a carcass for encasing a tubular member, said method comprising:providing a driven rotor having a front face, said driven rotorrotatable about a pivot axis; positioning a spool mandrel eccentricallyon said driven rotor, said spool mandrel adapted to rotatably mount aroll of coiled strip material; and preventing kink deformation of saidstrip material during the formation of said carcass using an anti-kinkroll assembly, wherein said anti-kink roll assembly comprises a seriesof shaped roller bearings that contact an inner radius of said stripprior to a fold over point.
 32. The method of claim 31 furthercomprising mounting at least one counterweight on said front face ofsaid rotor for movement relative to said pivot axis, said at least onecounterweight being dynamically movable to at least partially balancethe changing weight of said roll of strip material as said stripmaterial is removed from said roll.
 33. The method of claim 31 furthercomprising mounting at least one pusher roll assembly mounted on saidfront face and contacting a portion of said strip material to partiallydeform the coiling of said strip material as said material is removedfrom said roll.
 34. The method of claim 31 wherein said roll of coiledstrip material is removably and rotatably mounted to said spool mandrel.35. The method of claim 31 further comprising mounting a roller assemblyto said front face for pre-deforming said strip material prior tofeeding said strip material into profile-forming roller assemblies,wherein said profile-forming roller assemblies are adapted to form saidstrip material into an S-shape capable of interlocking with anadjacently formed profile edge.